JUst to share my thoughts. I was also looking for a good calibration shop and I checked the yellow pages. Four shops looked good and they are Betan, Central Diesel, Denso and Zexel (in alphabetical order). I suggest you call them for estimates. I guess that they all use original or quality replacement parts with warranties. Another consideration, aside fron the cost, is their proximity to you. You never know if you need to bring your rig back for adjustments or what. Sabi nga, tao lang at pwedeng magkamali.